IgE is a class of antibody involved in allergic reactions. These reactions occur when an individual who has produced IgE antibody in response to an innocuous antigen (allergen sensitisation) subsequently encounters the same allergen. The allergen triggers the activation of IgE-binding mast cells in the exposed tissue leading to a series of responses that are characteristic of allergy.
IgE is the immunoglobulin associated with Type I hypersensitivity reactions, which include asthma, allergic rhinitis (‘hay fever’), allergic conjunctivitis, urticaria and other allergies. Over-expression of this antibody is responsible for a substantial amount of human disease ranging from mild hay fever to life-threatening conditions such as severe asthma, peanut allergy and anaphylactic reactions to drugs such as penicillin. Activation of IgE triggers the response of cells such as mast cells in the skin, eyes, nose and bronchial tree.
Current approaches aimed at counteracting the unwanted effects of IgE activation include anti-IgE vaccines and anti-IgE monoclonal antibodies. The former are largely experimental. The anti-IgE monoclonal antibody approach has been more successful, although at present there is only a single example on the market (omalizumab, brand name Xolair®).
Thus it can be seen that a novel source of IgE modulators would provide a contribution to the art.